Optimization of ecofriendly synthesis of Ag nanoparticles by Linum usitatissimum hydrogel using response surface methodology and its biological applications

In the current study, the silver nanoparticles are green synthesized using reducing and stabilizing potential of aqueous extract of Linseed. The Response Surface Methodology (RSM) along with central composite design (CCD) was used to evaluate the influence of various independent variables like the concentration of silver nitrate (AgNO3), Linseed Hydrogel (LSH) suspensiot not used to find out the relative influencn percentage, sonication of LSH suspension, and exposure of reaction mixture to the sunlight on the response variable. RSM interpretation revealed that the results of all experiments were best fitted into a quadratic polynomial model with R2 value 0.9978 with SD 0.0018 for all responses. The optimized preparation conditions for LSH-Ag nanoparticles were concentration of AgNO3 (8.68 mM), LSH suspension percentage (0.73%), sonication time (5.29 min), and exposure to sunlight (69.52 min). The resultant LSH-Ag NPs were characterized using UV-Vis spectroscopy, ATR-FTIR, BT-90 nano size analyzer, PXRD, and SEM. These results illustrated that LSH-Ag NPs had a spherical shape, average size 34.47 nm, maximum absorbance at 423 nm, polydispersity index 0.063. Afterward, the anti-bacterial and anti-biofilm activity of LSH-Ag NPs was investigated against E. coli and B. subtilis whereas scavenging activity of 84.2% was shown by NPs with DPPH assay. The result of biological activities proposed synthesized NPs as apposite material having capability to be used as biological agent. The biological potential can be depicted by its phytochemical profile having total phenolic and flavonoid contents as 84.9 mg GA/g and 45.9 mg RU/g respectively. The thin film of synthesized NPs possesses tiny cavities that suggested it to use in drug delivery system.